Asteroid won't hit planet tomorrow

Updated
February 15, 2013 19:08:00

A big asteroid will only narrowly miss Earth when it passes our planet in the early hours of tomorrow morning. The best place to view the passage of the asteroid is Indonesia, where keen-eyed early risers have the chance to see the space rock whizzing past at a distance of 28,000 kms. Otherwise, the event will be monitored and webcast by American space agency, NASA.

TIM PALMER: A large asteroid will, in galactic terms, only narrowly miss Earth when it passes our planet in the early hours of tomorrow morning. For such a major and rare phenomenon it has a rather prosaic name - 2012 DA 14.

The best place to view the passage of the asteroid is Indonesia, where keen-eyed early risers have the chance to see the space rock whizzing past at a distance of 28,000 kilometres.

For the convenience of the rest of human kind, the event will be monitored and webcast by the American space agency, NASA.

Peter Lloyd reports.

(Sound of music - "Also sprach Zarathustra")

VARIOUS MOVIE QUOTES: Look, up in the sky! It's a bird... It's a plane... It's, it's! It's just a stupid boulder... It's not just a boulder, it's a rock, a rock. A rock.

PETER LLOYD: Whatever it is, it's a close shave for humanity if you're thinking really big, like Paul Floyd in Canberra.

He's a school teacher and amateur astronomer. This means that while he holds no academic qualification in professional astronomy, he does have the virtue of being able to explain complex things to small children.

PAUL FLOYD: Alright, well basically we've got what's known as an asteroid, or whatever astronomers prefer to call minor planets. Basically, if you're a Star Wars fan, picture a very large 50 metre diameter piece of rock spinning through space.

PETER LLOYD: How did you know I was a Star Wars fan?

PAUL FLOYD: Ah look, I don't know. I think everyone is nowadays. Star Wars has had a little bit of a reinvention. I always picture, when I think of asteroids, the Millennium Falcon zipping between the asteroids in the asteroid belt, which actually as an aside is quite different to the reality. Space is quite large and asteroids are actually nowhere near each other.

PETER LLOYD: And those are made of polystyrene.

PAUL FLOYD: Ah yes, yes. This one is not made of polystyrene and coincidentally, I mean, if it did happen to hit the Earth, which of course it's not going to - NASA's established the orbit to I think a three kilometre accuracy - it'd probably explode in the upper atmosphere, wipe out about 2,500 hectares of whatever was underneath it.

So that actually happened in 1908 with an asteroid over Tunguska, Siberia.

PETER LLOYD: You're quite the asteroid tragic aren't you?

PAUL FLOYD: I am. Look, these things are actually quite amazing. Like, you know, if you go back about 10, 20, 30 years, people used to think of asteroids as a big lump of rock and that's it, but they're actually a lot more interesting.

The Japanese landed a probe on an asteroid going back about five years, and the photograph they took as they were coming in to land, to collect a sample, actually showed, I think it was a 30 metre asteroid from memory, this asteroid wasn't a solid piece of rock, it was actually just bits of rock which were loosely gravitationally hung together. So they're actually quite complicated beasts.

What's interesting about 2012 DA 14 is basically if, say, you're in Indonesia which is the ideal place to see it, and you had good eyesight, you would be able to see a very, very faint star passing overhead.

So the next time that we know of an asteroid that's going to pass close enough to the Earth to be visible to the unaided eye is 2029 and that's an asteroid called Apophis.

I hope to be in Africa for that, because basically it'll be, let's see, from memory it's about 250 metres in diameter, that will pass overhead. It'll look like a third magnitude star so not quite as bright as the fifth brightest star in the Southern Cross.

So basically, this one's unusual in that it's the brightest known one that'll happen until 2029.